Building construction projects (including their planning, design, construction, startup, turnover, and operations phases) are generally managed haphazardly, and are often based only on the expertise or skill of those who are responsible for and managing the various phases. In essence, most building construction projects rely on the discretion of the owner, designers and builders to ensure that all of the project phases are properly and timely completed. It is evident that mere reliance on discretion is insufficient to assure quality as each phase is executed. A survey by the Lawrence Berkeley National Laboratory in 1996 indicates that buildings in the United States have approximately 15% of their components misinstalled (or never installed in the first place), and approximately 40% have control problems such as improperly tuned environmental systems. Additionally, these statistics may underestimate the degree of construction error since many improper or missing installations are never found. Those that are found are difficult to repair or change after installation is complete. Empirical and anecdotal data has indicated that it takes approximately two years after occupancy to identify and fix most building construction problems, and by that time, it may be difficult or impossible to have the building owner get the builders to perform modifications, equipment replacement, control sequence changes and repairs to meet the owner's project requirements. Additionally, the builders or other repair personnel will usually have a more difficult time making repairs because of their diminished familiarity with the project owing to passage of time, as well as the fact that the building is in service.
Several methods have been used to help ensure that construction projects were being delivered per the specifications of construction design documents and/or per project or contractual needs, and these methods may be applied to construction projects that are done by either an independent contractor or in-house personnel. Monitoring of in-house projects is especially typical at industrial plants; among real estate owners, developers, and managers of commercial property; large retail organizations; and in large commercial and governmental organizations. In almost all cases, quality assurance is related to performing inspections and testing at the end of the project. For example, when large components or systems have undergone complete installation, they are commonly tested to determine if they are operable. As another example, inspection “walk-throughs” by senior skilled personnel are common in construction projects to see whether construction is proceeding properly. However, these methods are generally focused on “absolute” functionality: whether the installation works in an absolute sense, rather than whether it functions as per the building owner's project intent (i.e., the building owner's project requirements, expectations, and desires, as discussed later). Further, they generally rely on a subjective opinion or superficial appearance of functionality, rather than on an objective or statistical quality assessment. Additionally, these methods are generally implemented only at the installation/construction phase, and are not extended to all phases of construction project delivery, including planning, design and operations phases. These methods are also problematic in that they assume that any error can be detected and corrected at any stage, especially the late construction stage of the delivery process. However, this is not true for most aspects of planning, design and construction, since many errors are as a practical matter uncorrectable once initiated, or are at least highly unfeasible to correct in terms of cost, reconstruction, and/or manpower. Further, while high quality should be provided if 100% inspection is provided on a regular basis as construction proceeds, it has been well documented that 100% review is not achievable within reasonable cost and time. Thus, most quality practice and research has been focused on determining an acceptable balance between low review of many items versus accurate review of a few items, with the balance being struck by statistical sampling methods.
The desire for successful delivery of construction projects has led to the implementation of many new quality assurance methods, including assigned project managers; construction management; Agency Construction Management; teaming; testing and balancing contractor; destructive and non-destructive testing; performance testing; critical path management; value engineering; construction quality control; automated data management, and other related methods. In addition, the use of the “sole responsibility” approach to project delivery—i.e., assigning responsibility for certain tasks or construction phases to a single person, contractor, or other entity—has been implemented to reduce conflicts between planning, design, and construction. The sole responsibility concept, while seemingly simplistic, should theoretically enhance quality over the traditional “shared responsibility” concept of construction since each party's role is more clearly defined, and responsibility is centralized in identified parties who will therefore have a greater incentive to ensure quality. Sole responsibility has been implemented by methods such as design-build project delivery and performance contracting, wherein the quality assurance responsibility is transferred to the design-build contractor or performance contractor. However, since these parties use the same quality assurance methods used by other construction projects, and since they frequently have an internal division of responsibility under one overall management responsibility, implementation of the sole responsibility concept generally results in only a moderate advance in quality. In essence, while the theory of sole responsibility seems simple and straightforwardly implemented, in practice it is difficult to apply and it does not resolve unsatisfactory problem resolution. The same applies to “teaming”, where there are still a number of team members to blame when the delivered construction project does not work or falls short of the project owner's expectations.
As an extension of the foregoing concepts, recent years have seen owners and those responsible for improving the delivered quality of construction projects implement a commissioning process which assigns a single entity to manage quality assurance and verification of the owner's project requirements and/or project intent at all phases of the project delivery. The entity or person managing this process is typically known as a “commissioning authority” or “commissioning agent.” In cases where the process is identified as something other than the commissioning process, the managing entity might be identified by different names, usually something like “construction quality manager.” In essence, the managing entity serves as a representative of the building owner to see that the construction project is efficiently and cost-effectively carried out as per the owner's project intent. The managing entity or commissioning authority reviews the construction project during all phases, and reviews the work done by planning, design, construction and operations personnel, often with the assistance of a checklist and/or the construction plans to see that the construction process is running smoothly. Frequently on large projects the commissioning authority is a number of people lead by a designated “owner's commissioning authority”. This process has improved quality assurance, but it still lacks the ability to effectively implement quality control using statistical tools, largely because it does not accomplish continuous and full knowledge of the current status of the project, nor does it implement objective and unbiased methods of evaluating the current quality of the project.
As previously noted, another flaw with prior quality assurance methods is that they tend to focus on absolute operability (i.e., meeting identified project specifications), rather than on the owner's project intent. Project intent extends beyond building specifications to the underlying issue of the functionality of the building for its intended purpose. To illustrate, the project intent of a school is (broadly) to enhance learning, whereas the project intent of an office building is to enhance productivity; thus, each building may have different demands in terms of lighting, noise, number and accessibility of electrical/data/water outlets, fire/safety egress, etc. Project intent therefore includes items such as space, comfort, safety, productivity desires, costs, aesthetics, sustainability, flexibility, indoor air quality, image, operating costs, energy efficiency, and other functional needs that the user or owner may have of the building. As examples, an owner of a school building may have elements of project intent such as no change orders during construction; no changes in the first year of operations; or student learning 10% higher than the average of existing schools after the building is placed in operation. Some of these elements may not be closely correlated with the building design, but they are the in owner's needs and goals that should be addressed in planning and design if they are to be achieved. Unfortunately, since the expectations of owners are difficult to identify and document as opposed to more “tangible” physical building specifications, most design and construction efforts take no or minimal account of project intent. This is problematic and expensive because later correction/modification of the constructed project to meet project intent, as well as the continued maintenance required to compensate for these problems, adds significantly to the costs of initial construction and later upkeep.
Construction costs are also enhanced by the disorderly way in which construction progresses. In general, it is difficult to run construction tasks in parallel with each other in any specific area of a construction project, for example, for one contractor to install piping in one area of a building simultaneously with another contractor installing the ductwork in the same area. Thus, construction teams usually handle tasks sequentially, with one team moving in to install certain components once the prior team has completed installation of other components. However, since some teams may not (or may not be able to) efficiently handle installation—as by installing components with the intent of freeing certain areas of the project for work by other teams as soon as possible—the construction project may be dramatically slowed by “bottlenecks” in the construction process. This also has a significant impact on construction costs since some construction teams and/or contractors may need to sit idle until prior teams have completed their tasks. This timing problem has been an issue of significant concern among owners, construction managers, engineers and architects for many years, and its ramifications are reflected by United States Department of Commerce data indicating that the AEC (architectural, engineering and construction) industry has had a 16% reduction in productivity between 1970 and 2000, while manufacturing has had a 89% increase in productivity in the same period in the United States. Prior patents dealing with construction task scheduling or related subjects are exemplified by U.S. Pat. No. 5,016,170 to Pollalis et al., U.S. Pat. No. 5,761,674 to Ito, U.S. Pat. No. 4,019,027 to Kelley, and U.S. Pat. No. 4,700,318 to Ockman. U.S. Pat. No. 5,189,606 to Burns et al. and U.S. Pat. No. 5,950,206 to Krause are also of interest. Unfortunately, these prior “construction schedules” and other manual methods for tracking the completion of construction can be time-intensive and costly to complete, subject to error, and difficult to adapt to projects which vary from a “standard” project for which the method was originally adapted.